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Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1at and 19.7at 8 . A clear signal is observed in the diphoton channel at a mass close to 125 with a local significance of , where a significance of is expected for the standard model Higgs boson. The mass is measured to be , and the best-fit signal strength relative to the standard model prediction is . Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.

A search for the standard model Higgs boson decaying to a W-boson pair at the LHC is reported. The event sample corresponds to an integrated luminosity of 4.9 fb −1 and 19.4 fb −1 collected with the CMS detector in pp collisions at √ s = 7 and 8 TeV, respectively. The Higgs boson candidates are selected in events with two or three charged leptons. An excess of events above background is observed, consistent with the expectation from the standard model Higgs boson with a mass of around 125 GeV. The probability to observe an excess equal or larger than the one seen, under the background-only hypothesis, corresponds to a significance of 4.3 standard deviations for m H = 125.6 GeV. The observed signal cross section times the branching fraction to WW for m H = 125.6 GeV is 0.72 +0.20 −0.18 times the standard model expectation. The spin-parity J P = 0 + hypothesis is favored against a narrow resonance with J P = 2 + or J P = 0 − that decays to a W-boson pair. This result provides strong evidence for a Higgs-like boson decaying to a W-boson pair. Finding such a signal in the complex environment of a hadron collider is not straightforward. A complete reconstruction of all the final-state particles is not possible because of the presence of neutrinos which are not directly detected. Kinematic observables such as the opening angle between the two charged leptons in the transverse plane, the dilepton mass, and the transverse mass of the system of the two leptons and the neutrinos, can be used to distinguish not only the Higgs boson signal from background processes with similar signature [17,18], but also between the SM Higgs boson hypothesis and other narrow exotic resonances with different spin or parity. Phenomenological studies of the amplitudes for the decay of a Higgs or an exotic boson into the WW final state demonstrate a good sensitivity to distinguish between the SM Higgs boson hypothesis (spin-parity 0 + ) and a spin-2 resonance, which couples to the bosons through minimal couplings, referred to as 2 + min [19]. Some sensitivity has also been shown with this final state to distinguish between the 0 + and the pseudoscalar 0 − boson hypotheses. Keywords: Hadron-Hadron Scattering, Higgs physics-1 - JHEP01(2014)096Searches for the SM Higgs boson in the H → WW final state at the LHC have previously been performed using data at √ s = 7 TeV by CMS [20][21][22], excluding the presence of the SM Higgs boson at the 95% CL in the mass range 129-270 GeV, and by ATLAS [23], excluding the mass range 133-261 GeV. Using their full dataset at 7 and 8 TeV, ATLAS have reported a H → WW signal with a statistical significance of 3.8 standard deviations [24] as well as evidence for the spin zero nature of the Higgs boson [25].This paper reports a measurement of the production and properties of the Higgs boson in the WW decay channel using the entire dataset collected by the CMS experiment during the 2011 and 2012 LHC running period. Various production modes, using events with two or three charged leptons ( ), electrons o...

Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise

A search for new physics is performed based on events with jets and a pair of isolated, same-sign leptons. The results are obtained using a sample of proton-proton collision data collected by the CMS experiment at a centre-of-mass energy of 8 TeV at the LHC, corresponding to an integrated luminosity of 19.5 fb −1 . In order to be sensitive to a wide variety of possible signals beyond the standard model, multiple search regions defined by the missing transverse energy, the hadronic energy, the number of jets and bquark jets, and the transverse momenta of the leptons in the events are considered. No excess above the standard model background expectation is observed and constraints are set on a number of models for new physics, as well as on the same-sign top-quark pair and quadruple-top-quark production cross sections. Information on event selection efficiencies is also provided, so that the results can be used to confront an even broader class of new physics models. 8 Limits on models of new physics and on rare SM processes 109 Information for additional model testing 19 Summary 22The CMS collaboration 27 IntroductionIn the standard model (SM), proton-proton collision events having a final state with isolated leptons of the same sign are extremely rare. Searches for anomalous production of same-sign dileptons can therefore be very sensitive to new physics processes that produce this signature copiously. These include supersymmetry (SUSY) [1][2][3], universal extra dimensions [4], pair production of T 5/3 particles (fermionic partners of the top quark) [5], heavy Majorana neutrinos [6], and same-sign top-quark pair production [7,8]. In SUSY, for example, same-sign dileptons occur naturally with the production of gluino pairs, when each gluino decays to a top quark and a top anti-squark, with the anti-squark further decaying into a top anti-quark and a neutralino. In this paper we describe searches for new physics with same-sign dileptons (ee, eµ, and µµ) and hadronic jets, with or without accompanying missing transverse energy (E miss T ). Our choice of signatures is driven by the following considerations. New physics signals with large cross sections are likely to be produced by strong interactions, and we thus expect significant hadronic activity in conjunction with the two leptons. Astrophysical evidence for dark matter [9] suggests considering SUSY models with R-parity conservation, which provides an excellent dark matter candidate -a stable lightest supersymmetric particle -1 -JHEP01(2014)163 JHEP01 (2014)163 (LSP) that escapes detection. Therefore, a search for this signature involves sizable E miss T due to undetected LSPs. Nevertheless, we also consider signatures without significant E miss T in order to be sensitive to SUSY models with R-parity violation (RPV) [10] which imply an unstable LSP. Beyond these general guiding principles, the choice of signatures is made independently of any particular physics model and, as a result, these signatures can be applied also to probe non-supersymmetric ex...